Recently [Roberto Barrios] got his hands on a Rohde & Schwarz EB200 monitoring and surveillance receiver that, despite its late 90s vintage, was in mint condition. Aside from damage to the main dial, that is, which was very much broken. With no off-the-shelf replacement available in 2023, the obvious answer was to get a close-enough dial knob with the rough proportions and use a lathe to machine it into shape. Initially, [Roberto] had used some filler material to replace the front of the original knob that was missing, but this was a decidedly inferior tactile experience with questionable long-term reliability.
The challenge in replacing the original knob with a proper replacement was in how the dial knob is mounted on the receiver, as an internally threaded shell that goes on the internal dial encoder assembly. With a lathe at his behest, taking an off-the-shelf dial knob that accepts a 6 mm shaft and turning it into a compatible knob was a straightforward affair. Removing the excess material and creating the internal 1 mm pitch thread allowed the newly made knob to fit on the receiver like an OEM part. The only niggle was having to remove 1.8 mm off the face of the brass body to get the knob to sit close to the front panel.
Unlike the old patched-up knob, this new one is fully out of metal and has the absolutely essential feature of the recessed area for easy fine-tuning. Although perhaps not the most exciting fix for old gear, it’s decidedly essential to keep it functional.
The core of the build is a hefty wooden base, something that is a core component of any good machine tool. It was built from a large beam sourced from a ship supply house, and originally used to hold a sturdy vice. It eventually gained a motor from a cement mixer when [bartworker] decided it should be converted into a lathe. From there, it was further equipped with a sliding support for larger workpieces, allowing [bartworker] to lathe some seriously big stock.
The lathe is very much an ever-evolving thing, and [bartworker] has used it to share the joys of woodworking with his family and friends. As a demonstration of its abilities, the lathe was able to produce a handsome handle for [bartworker]’s axe.
If there’s one thing we’ve learned from [Chris] at Clickspring, it’s that a clockmaker will stop at nothing to make a clock not only work perfectly, but look good doing it. That includes measures as extreme as this complete re-toothing of a wheel from a clock. Is re-toothing even a word?
The obsessive horologist in this case is [Tommy Jobson], who came across a clock that suffered a catastrophic injury: a sudden release of energy from the fusee, the cone-shaped pulley that adjusts for the uneven torque created by the clock’s mainspring. The mishap briefly turned the movement into a lathe that cut the tops off all the teeth on the main wheel.
Rather than fabricate a completely new wheel, [Tommy] chose to rework the damaged one. After building a special arbor to hold the wheel, he turned it down on the lathe, leaving just the crossings and a narrow rim. A replacement blank was fabricated from brass and soldered to the toothless wheel, turned to size, and given a new set of teeth using one of the oddest lathe setups we’ve ever seen. Once polished and primped, the repair is only barely visible.
Honestly, the repaired wheel looks brand new to us, and the process of getting it to that state was fascinating to watch. If the video below whets your appetite for clockmaking, have we got a treat for you.
The low-cost servo motor in [Clough42]’s lathe’s electronic leadscrew bit the dust recently, and he did a great job documenting his repair attempts ( see video below the break ). When starting the project a few years ago, he studied a variety of candidate motors, including a ClearPath servo motor from Teknic’s “Stepper Killer” family. While that motor was well suited, [Clough42] picked a significantly lower-cost servo motor from China which he dubbed the “Stepper Killer Killer”.
He does a very thorough post-mortem of the motor’s integrated servo controller, checking the circuits and connections on the interface PCB first. Not finding any obvious problem, he proceeds to the main PCB which contains the microcontroller, motor driver transistors, and power supplies. There is no visible damage, but a check of the logic power supply shows 1.65V where 3.3V is expected. Looking at the board with a smart-phone mounted IR camera, he quickly finds the bad news — the microcontroller has shorted out.
A regular pair of pliers is fine most of the time, but for delicate work with squarish objects you can’t go wrong with a pair of parallel pliers. [Neil Paskin] decided to make his own pair from scratch. (YouTube)
The jaws were machined down from round stock in [Paskin]’s mill before heat treating and tempering. The steel portions of the handles were cut from 16 gauge plate steel and half of them were stamped on a fly press to make the bridging section around the pivot bolt. The filler for the handles is copper on one side and brass on the other as [Paskin] didn’t have enough brass of the correct size to do both.
The steel and filler were joined with epoxy and copper pins before beveling the edges and sanding to give a comfortable contour to the handles. The bolts for the pliers started as ordinary hex bolts before being machined down on the lathe to a more aesthetically-pleasing shape and size. The final touches included electrolytically etching a logo into the bridge and then spraying down the pliers with a combination lubricant and corrosion preventative spray. This is surely a pair of pliers worth handing down through the generations.
While some people are happy with a simple coffee table to hold their snacks while watching Star Trek reruns, others want their furniture to go where no furniture has gone before. [Olivier Gomis] has definitely satisfied this need with his Wormhole Coffee Table. [YouTube]
The complicated shape and curvature of a (3D representation of a) wormhole isn’t easy to create, but [Gomis] managed to carve one without the aid of a CNC or 3D printer. Starting with walnut planks and maple veneer laminated together, he created a grid stackup to replicate the common representation of spacetime as a 2D grid. Using various arrangements of these grids, he built up the central section of the wormhole which looked like a low poly vase before he put it on the lathe for turning.
The lathe work on this build is simultaneously impressive and terrifying. Turning down the central portion of the wormhole required working between two large spinning squares of walnut, which [Gomis] admits was “scary.” Multiple custom jigs were required to keep parts flat and deal with the extreme curvature of the inside of the wormhole’s opening. If that weren’t enough, if you look down the wormhole, he has installed a set of LED lights that show the spacetime grid continuing on to parts unknown.
Moving such a stout piece of equipment cannot simply be done by recruiting a few friends and remembering to lift with the legs. This kind of machinery cannot be moved and handled except with the help of other machines, so [Ben] and friends used an engine hoist with a heavy-duty dolly to get it out of the basement it was in, and into the bed of a pickup truck. Separating the lathe from its base helped, as did the fact that the basement had a ground-level egress door which meant no stairs needed to be involved.
One also has to consider the machine’s ultimate destination, because not all floors or locations can handle nearly a thousand pounds of lathe sitting on them. In [Ben]’s case, that also meant avoiding a section of floor with a maintenance trapdoor when moving the lathe into the house. Scouting and knowing these things ahead of time can be the difference between celebratory pizza and deep dish disaster. Pre-move preparation also includes ensuring everything can physically fit through the necessary doorways ahead of time; a task that, if ignored, will eventually explain itself.
With that all sorted out, [Ben] dives into cleaning things up, doing function checks, and in general getting the lathe up and running. He provides some fantastic photos and details of this process, including shots of the 70s-era documentation and part diagrams.